Inflammation inhibiting bis-carbamate composition

ABSTRACT

P-aminophenol-bis-carbamate derivatives which are suitable as active ingredients in drugs, particularly for inhibiting inflammation, the production of such active ingredients, and drug formulations containing the active ingredients.

' United States Patent [191 i Rohr et. al. i Y v [451 Nov. 1s, 1975 INFLAMMA'I'ION INHIBITING [56] References Cited BIS-CARBAMATE COMPOSITION UNITED STATES PATENTS Inventors: Wolfgang Ruhr, Mannheim: 3,399,265 8/1968 Szabo ..,424/3oo Albrecht Franke, Ludwigshafen; 3.450.745 6/1969 Payne et al. 424/300 Hubert Giertz, Limburgerhof; Y 3,546,343: 12/ 1970 Payne et al. 424/300 August Amann, Ludwigshafen, all of v Germany Primary ExaminerJerome .D. Goldberg r [73] Assigneet Badische Anflim & soda Fabrik Attorney, Agent, or Firr nJ0hnston, Kcil, Thompson Aktiengesellschaft, Ludwig'shafen & Shurtleff (Rhine), Germany I v 22 Filed: Aug. 30, 1972 I ABSTRACT [21] APPL NO: 284 760 P-aminophenoLbis-carbamate derivatives which are suitable as active ingredients in drugs, particularly for s inhibiting inflammation, the production of such active [52] US. Cl. 424/300; 260/471 C ingredient and drug formulations containing the acll'lt. Clfive ingredients [58] Field of Search 260/471 C; 424/300 2 Claims, No Drawings v 3,920, 3. INFLAMMATION 'INHIB'ITING. BTSCARBXMATE i coMPostTto in which R and R are identical or different aliphatic radicals which maybear phenyl as a substituent.

The unsubstituted or substituted aliphatic radical may be linear, branched or cyclic, saturated or unsaturated. Examples of aliphatic radicals are accordingly alkyl radicals, particularly alkyl of one to six carbon atoms such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl,'s-butyl, t-butyl, pentyl and hexyl. The cyclic. aliphatic radicals may be those of five to eight carbon atoms, for example the cyclopentyl, cyclohexyl and cyclooctyl i'a tdi cals. The cycloaliphatic radicals may also be bis-cycles or endo -cycles. Phenyl is the preferred substituent of the aliphatic radical, an example being benzyl. The radicals may have one or more unsaturations, and maycontain do'uble bonds or triple bonds such'as in the all'yl, m'ethallyl, bitten- (l )-yl-(3), buten (2)-yl- (3), proparg yl, but' n-g la butyn-(2)-yl- 3 or' 3-rnethylbutyn-(l )-yl-(3) radical.

CompOu nds having. alkylof one to four carbon atoms, cycloalkyl of five to eight carbon atoms, particularly cyclohexyl, and ben zyl are preferred as R. Lower alkyl, of. on e' to about four carbon atoms, particularly methyl is preferred as the radical R The new compounds may be preparedfor example by the following methods: V by reaction of 2-methyl,-}hydroxyphenylcarbamates of the general formula:

(which may be in the form of an alkali metal salt) a. with an isocyanate of the formula R'N=C=O or b. with a carbamyl chloride of the formula c. with phosgene tojform the corresponding chloroformate which is then condensed with an amine deriva-' tive of the formula: RNH 6 or by reaction of d. 3-methyl-4-nitrophenol with an isocyanate of the formula RN=C=O to form a 3'-methyl-4-nitrophenyl carbamate of the formula;

whereupon the nitro group is reduced, the resultan amine converted into the isocyanate of the formula and this reacted with an alcohol to form the desireci carbamate,

e. by reaction of 3-methyl-4-nitrophenol with phosgene with the formation of 3-methyl-4-nitrophenyl chloro formate:

followed by reaction with an amine derivative of the formula: V

RNH to form a 3-methyl-4-nitrophenyl carbamate which as described under (d) is converted via the stage of the amine and the isocyanate into the desired carbamate, R and R in the general formulae under (a) to (e) having the meanings given above.

The reaction according to (a) is conveniently carried out in an organic solvent, for example tetrahydrofuran or chloroform and if desired with the addition ofa catalyst, preferably an organic base, for example triethylamine.

Reaction according to (b) is conveniently carried out in an organic solvent, for example pyridine or methyl isobutyl ketone, with or without the addition of an acidbinding agent such as an organic base, for example a tertiary amine. preferably triethylamine. or inorganic bases, for example caustic soda solution.

Reaction with phosgene according to'(c) is carried out conveniently in an organic solvent, for example ethyl acetate or dichloroethane and at a temperature of from about 0 to 50C. if desired with an addition of an inorganic or organic base, for example caustic soda solution or N,N-dimethylaniline. For the further reaction according to (c) withthe amine an excess of the same may be used as reaction medium or water or an organic solvent. it is convenient to add an acid-binding agent, for example an organic or inorganic base such as triethylamine or sodium carbonate.

For the reaction according to (d) the first stage is conveniently carried out in an organic solvent. for example tetrahydrofuran or ethyl acetate and if desired with the addition of a catalyst, preferably an organic base, for example triethylamine. The following reduc- .tion stage may be carried out by a conventional method, for example by catalytic reduction or by treating 3-methyl-4-nitrophenyl carbamate with another reducing agent such as hydrogen sulfide or sodium sulfide. The amine obtained is converted by a conventional method into the corresponding isocyanate, for example by reaction with phosgene in an inert organic solvent such astetrahydrofuran or ethyl acetate, if desired in the presence of an acid-binding agent, preferably a tertiary organic base such as triethylamine.

Reaction with phosgene according to method (e) is onveniently carried out in an inert organic solvent.- for xample ethyl acetate or l.2-dichloroethane at a temerature of from about to 50C, if desired in the 4 It has been extensively tested and found to be particularly important. 1

The following compounds may be obtained in an analogous manner:

resence of an inorganic or organic base such as causic soda solution or N,N-dimethylaniline. Further reacions according to method (e) to form the desired car- 1 2 amate are carried out under the reaction conditions R 'gpecified under (c) and (d). O Q

The Z-methyl-4-hydroxyphenyl carbamates necesary for the reactions (21) to (c) as starting materials my be prepared for example by reaction of Z-methyl- Example 1 -hydroxyaniline with a chloroformate in water or an 2 CH3 CH I38 Ml rganic solvent such as dichloroethane with the addi- 3 CZHB CH1 126 to 128 i011 of an inorganic base such as sodium bicarbonate or 4 .1 3 127 to I28 n organic tertiary base such as 'triethylamine. 2 g g gl The new compounds have valuable pharmacological 7 benzyl i-CQH, 150 to I52 TOPCI'IICS. In particular. they act as inflammation ing g5:1elhy|bmyn.l )|3 21 lbitors, anodynes and febrifuges. They also act on the 10 i CH7 149 to 153 entral nervous system and are capable of decisively icreasing the separation of sodium ions in urine. The ubstances have low toxicity and do not cause any hange in haemoglobin. The N-(2-methyl-4-hydroxyphenyl)-methyl carba- The inflammation inhi iting and analg sic ffects mate used as starting substance may be obtained in the ave been compared with those of phenacetin. There is following manner: clearly stronger inflammation inhibiting effect but the A mixture consisting of 49.2 parts by weight of 4- nalgesic effect is not increased. The fact that the comamino-3-methylphenol, 300 parts by weight of dichloounds according to the invention, in a dosage which in roethane and 35.3 parts by weight of sodium bicarbon- 1e case of phenacetin causes severe methaemoate is heated to 35C and 39.7 parts by weight of methyl lobinemia, does not affect haemoglobin is particularly chloroformate is added over 2 hours. The whole is nportant. stirred for another 2 hours at C for further reaction. The compounds may be applied in conventional pe- The cold reaction mixture is treated with dilute hydroaral formulations. The active ingredients of this invenchloric acid and water. and the organic phase is dried on may be combined with other active ingredients and with magnesium sulfate and then concentrated in ray also be used together with phenacetin. 35 vacuo. The dark colored residue is recrystallized from The production of the new compounds is illus rat d benzene with an addition of activated charcoal. Melt- 1 the following Examples. ing point: 93 to 96C.

The inflammation inhibiting properties are deter- EXAMPLE I mined according to the method of C. A. Winter, E. A. N-(2-methyl-4-benzylcarbamoyloxyphenyl)-methyl Risley and G. W. Nuss described in Proc. soc. Exp.

carbamate Biol. Med., 1 l 1, 544 (1962). In this method an inflam- A solution of 18.5 parts by weight of N-(2-methyl-4- i swelling is in the hind paw of rats by ydroxy-phenyl)-methyl carbamate in 80 parts b in ection of carrageen n, which can be lessened or pre- 'eight of tetrahydrofuran has added to it 0.5 part by y mflammatfon f Substances" Thls 'eight of triethylamine and 14 parts of benzyl isocyaexpressed m the Y P Table as oedema ate while stirring at 20C. The reaction mixture is mhlbmon m after peroral adm'mstrauon: :irred for five hours at C to complete the reaction. he deposited reaction product is suction filtered and CH )gether with the fraction obtained from the mother li- 5O 1 3 2 uor by concentration is recrystallized from ethyl ace- R -N'H-C-O NH-g-OR lte. Melting point 144 to 147C. O The compound has the following structural formula R R2 Oedema inhibition in Z on peroral administration of mg/kg 400 200 100 50 20 CH CH, 50 43 35 C,H CH 7 v 27 10.5 nC -,H CH 54 35 30 C H, CH CH 59 50 3s phenacetin (commercial grade) 74 46 27 CH We claim: I 3 1. An inflammation inhibiting composition compris- CH NH C QCH ing an effective anti-inflammation amount of N-( 2- 2 g 8 3 methyl-4-benzyl-carbamoyloxyphenyl)-methyl carbamate in a perorally administrable drug formulation.

3,920,829 v 6 2. An inflammation inhibiting composition comprising an effective anti-inflammation amount of N-(2- 'methyl-4-propyl-carbamoyloxyphenyl)-methyl carbav mate in a perorally administrable drug formulation; 

1. AN INFLAMMATION INHIBITING COMPOSITION COMPRISING AN EFFECTIVE ANTI-INFLAMMATION AMOUNT OF N-(2-METHYL-4-BENZYLCARBAMOYLOXYPHENYL)-METHYL CARBAMATE IN A PERORALLY ADMINISTRABLE DRUG FORMULATION.
 2. An inflammation inhibiting composition comprising an effective anti-inflammation amount of N-(2-methyl-4-propyl-carbamoyloxyphenyl)-methyl carbamate in a perorally administrable drug formulation. 